Detergent composition containing blend of mixed fatty acid derivatives

ABSTRACT

A fabric-washing detergent composition containing a mixture of soap and non-soap detergents and adapted for use in automatic washing machines has improved suds-controlling properties if the soap component is derived from a blend of fatty acids made up from, by weight: A. 25 TO 45% OF SATURATED FATTY ACIDS CONTAINING LESS THAN 16 CARBON ATOMS, B. 20 TO 40% OF SATURATED FATTY ACIDS CONTAINING 16 TO 18 CARBON ATOMS, C. 5 TO 20% OF SATURATED FATTY ACIDS CONTAINING MORE THAN 18 CARBON ATOMS, AND D. 10 TO 40%OF UNSATURATED FATTY ACIDS CONTAINING ON AVERAGE MORE THAN 16 40% OF ATOMS.

Ilnite- States Patent [191 McGrath et al.

[ DETERGENT COMPOSITION CONTAINING BLEND OF MIXED FATTY ACID DERIVATIVES [75] Inventors: Carol Beverley McGrath; John Warren Scanlon, both of Wirral,

England [73] Assignee: Lever Brothers Company, New

York, NY.

[22] Filed: Jan. 24, 1973 21 Appl. No.: 326,317

[30] Foreign Application Priority Data Jan. 28, 1972 Great Britain 72/4181 [56] References Cited UNITED STATES PATENTS 3,730,912 5/1973 Inamorato 252/121 X Jan. 21, 1975 OTHER PUBLICATIONS McBride, Chemical and Metallurgical Engineering, Dec. 1940, pp. 830 to 833 (TNlMS 260-398).

Primary Examiner-Leland A. Sebastian Attorney, Agent, or Firm-Arnold Grant [57] ABSTRACT A fabric-washing detergent composition containing a mixture of soap and non-soap detergents and adapted foruse in automatic washing machines has improved suds-controlling properties if the soap component is derived from a blend of fatty acids made up from, by weight:

a. 25 to 45% of saturated fatty acids containing less than 16 carbon atoms, b. 20 to 40% of saturated fatty acids containing 16 to 18 carbon atoms, c. 5 to 20% of saturated fatty acids containing more than 18 carbon atoms, and c1. 10 to 40%of unsaturated fatty acids containing on average more than 16 40% of atoms.

3 Claims, No Drawings DETERGENT COMPOSITION CONTAINING BLEND OF MIXED FATTY ACID DERIVATIVES The present invention relates to detergent compositions, and in particular it relates to fabric-washing detergent compositions which contain a proportion of soap and which are specifically adapted for use in automatic washing machines. The invention relates also to particular fatty acid blends and to soaps derived from such blends, which soaps are suitable for use in such detergent compositions.

Hereinafter, reference to a soap being derived from a fatty acid blend is used to include a soap which has been prepared by the direct neutralisation of a fatty acid blend by appropriate alkaline material, and also a soap which has been prepared by any other means, such as the saponification of fats and oils, wherein the fatty acid blend, salts of which compose the soap, may never itself have existed as a separate entity.

It is an essential requirement of a fabric-washing detergent composition which is intended to be used in an automatic washing machine that the detergent composition must have a suitable lather profile, ie the quantity of lather produced by a wash solution containing an optimum amount of the detergent composition, examined at the various temperatures at which that wash solution may be used, should never be inadequate or excessive. Although in most circumstances there is no real connection between the cleaning ability of a fabricwashing detergent composition and the quantity of lather a solution of that detergent composition produces, the consumer believes that there is such a connection and often assumes that a poor lather denotes an ineffective detergent composition or an insufficient quantity of the detergent composition in the wash solution. On the other hand, an excessive amount of lather can be a nuisance to the user of the detergent composition as, when the detergent composition is being used in a washing machine, the excessive lather may spill out of the washing machine or, in some cases, may cause the washing machine to mal-function.

Several conventional fabric-washing detergent compositions are formulated with these considerations in mind and such detergent compositions are often referred to as controlled-sudsing detergent compositions.

Conventional controlled-sudsing detergent compositions in general comprise a detergent-active component which is either a. a mixture of a nonionic component and soap, or

b. a mixture of a non-soap anionic component and soap, or

c. a mixture of both a nonionic component and a non-soap anionic component together with soap;

the controlled-sudsing properties of these detergent compositions is governed largely by their common feature, namely the soap in the detergent-active component.

Hitherto, the principal intention borne in mind when such controlled-sudsing detergent compositions have been formulated was that the controlled-sudsing detergent composition should not produce an excessive quantity of lather at high temperatures. This object has been achieved, but unfortunately the resultant detergent compositions possess disappointingly low lather performances at lower temperatures and this is now recognised as being an undesirable feature of a controlled-sudsing detergent composition. It is now recognised that a controlled-sudsing detergent composition ideally should produce, over the whole range of temperature under which it is used, a consistently adequate, but not excessive, level of lather.

Accordingly, it is an object of the present invention to provide a controlled-sudsing detergent composition which exhibits a degree of lather control at high temperatures which is sufficient for practical purposes but which at lower temperatures can produce a higher and more consistent level of lather than has been achieved with the use of hitherto conventional controlledsudsing detergent compositions.

It is a general feature of detergent compositions incorporating soap that, if the quantity of soap in such detergent compositions is increased, such detergent compositions become less readily soluble in water. This is particularly noticeable when the soap incorporates soap derived from saturated fatty acids containing 16 or more carbon atoms. Accordingly, a controlledsudsing detergent composition should contain the lowest quantity of long-chain saturated soap permissible consistent with the retention of the desired lathering performance of the detergent composition. Accordingly, it is a further object of the present invention to produce a controlled-sudsing detergent composition which contains as low a level as possible of such soap.

It is a further general feature of detergent compositions incorporating soap that, if the quantity of soap in such detergent compositions is increased, the lather produced by aqueous solutions of such detergent compositions becomes more'susceptible to the effects of water hardness. In general this is not dependent upon the carbon content of the soap, and accordingly it is a further object of the invention to produce a controlled sudsing detergent composition which contains as low a total level as possible of soap.

By the invention it has been found that improved controlled-sudsing properties can be imparted to a fabric-washing detergent composition if the soap component of the detergent composition is derived from a blend of four distinct groups of fatty acids as defined below.

The invention provides a blend of fatty acids, which blend is suitable for use in the form of a soap as an ingredient of a controlled-sudsing fabric-washing detergent composition, which blend consists of, by weight:

a. from about 20 to about 50%, preferably from about 25 to about 45%, and particularly preferably from about to about 40%, of saturated fatty acids containing less than 16 carbon atoms;

b. from about 20 to about 40%, preferably from about 25 to about of saturated fatty acids containing from 16 to 18 carbon atoms;

c. from about 5 to about 25%, preferably from about 10 to about 20%, and particularly-preferably from about 12 to about 18% by weight of saturated fatty acids containing more than 18 carbon atoms; and

d. from about 10 to about preferably from about 10 to about 30%, and particularly preferably from about 15 to about 25%, by weight of unsaturated fatty acids containing on average more than about 16 carbon atoms.

The invention includes a soap, preferably an alltali metal soap, derived from such a fatty acid blend.

The present invention also provides a controlledsudsing fabric-washing detergent composition from about to about 30% by weight of which comprises a detergent-active component, which detergent-active component itself consists ofa soap component together with a non-soap component and/or a nonsoap anionic component, the soap component being derived from a blend of fatty acids as defined above.

By way of example only, the various components of the fatty acid blend may be derived as follows:

The fatty acids comprising group (a) above may be derived predominantly from coconut fatty acids or from the fractional distillation of other natural or synthetic fatty acid mixtures. Preferably, at least 60% by weight of the fatty acids making a sample of group (a) should contain at least carbon atoms. The fatty acids comprising group (a) should not include more than trace amounts of fatty acids containing less than 6 carbon atoms.

The fatty. acids comprising group (b) above may be derived predominantly from hardened tallow fatty acids (comprising mainly stearic acid), or from the stearic fraction of distilled unhardened tallow fatty acids, or from palm oil which has been at least partially hardened.

The fatty acids comprising group (c) above may be derived predominantly from hardened fish oils, such as herring oil, or from vegetable oils such as hardened rape seed oil. The fattyacids comprising group (c) should not include more than trace amounts of fatty acids containing more than 24 carbon atoms.

The fatty acids comprising group (d) above may be derived predominantly from unhardened tallow fatty acids, or hardened or partially hardened oils which yield a high proportion of fatty acids containing more than 16 carbon atoms, such as palm oil and certain fish oils. The fatty acids comprising group (d) should not include more than trace amounts of fatty acids containing more than 24 carbon atoms.

It will be appreciated that, in general, each group of fatty acids will not be derived entirely from one particular source, but each particular source will contribute a major proportion of one particular group of fatty acids together with minor proportions of one or more other groups. For instance, the fish oils which may be used to provide the major proportion of the fatty acids.

in group (c) usually incorporate significant proportions of fatty acids having carbon contents down to 16 atoms, and wouldthus contribute towards the total of fatty acids in group (b). This is brought out further in the Examples.

The soaps which are derived from the above blends will in general be sodium soaps, but may if desired contain other cations such as potassium or, less preferably, ammonium or substituted ammonium. The soaps, where appropriate, may be prepared by direct neutralisation of the fatty acids by appropriate alkaline materials, or by saponification of the various fats by caustic alkalis, or by a combination of these techniques.

In a controlled-sudsing detergent composition of the invention, the soap component should comprise from about 1 to about and preferably from about 2 to about 10%, by weight of the detergent composition.

The non-soap anionic component of a controlledsudsing detergent composition of the invention will incorporate one or more non-soap anionic detergentactive compounds. The non-soap anionic component should comprise from about 0 to about 15%, preferably from about 1 to about 15%, and particularly preferably from about 4 to about 12%, by weight of the detergent composition.

The nonionic component of a controlled-sudsing detergent composition of the invention will incorporate one or more nonionic detergent-active compounds. The nonionic component should comprise from about 0 to about 20% by weight of the detergent composition.

Either the non-soap anionic component or the nonionic component must comprise at least about 1% by weight of the detergent composition.

In a controlled-sudsing detergent composition of the invention which contains no non-soap anionic component, the nonionic component should comprise preferably from about 8 to about 20%, and particularly preferably from about 10 to about 16%, by weight of the detergent composition. In this embodiment of the invention, the soap component should comprise preferably from about 1 to about 5% by weight of the detergent composition.

In a controlled-sudsing detergent composition of the invention which does contain a non-soap anionic component, the nonionic component should comprise preferably from about lto about 10%, and preferably from about 2 to about 8%, by weight of the detergent composition.

Typical suitable non-soap anionic detergent-active compounds are water-soluble or water-dispersible salts of various organic acids. The cations of such salts are generally alkali-metals, such as sodium and, less preferably, potassium, but other cations, such as ammonium and substituted ammonium, can be used if desired. Examples of suitable organic acids are: alkyl-benzene sulphonic acids, the alkyl chains of which contain from about 8 to about 20 carbon atoms, such as decyl-, dodecyl-, tetradecyl-, hexadecyland octadecylbenzene sulphonic acids, and the more usual commercially-available mixtures of such sulphonic acids, such as C1145 alkylbenzene sulphonic acids, the alkyl chains of these sulphonic acids preferably being linear as such compounds tend to be more readily biodegradable; the mixtures of sulphonic acids obtained by reacting linear and branched olefins, particularly linear cracked-wax or Ziegler alpha-olefins, containing from about 8 to about 22 carbon atoms, with sulphur trioxide; alkyl sulphonic acids obtained by reacting alkanes containing from about 8 to about 22 carbon atoms with sulphur dioxide/oxygen or sulphur dioxide/chlorine (followed by hydrolysis in the latter case), or by the addition of bisulphite to olefins, particularly linear cracked-wax or Ziegler alphaolefins, containing from about 8 to about 22 carbon atoms; alkyl sulphuric acids obtained by reacting aliphatic alcohols containing from about 8 to about 22 carbon atoms with sulphur trioxide; alkyl ether sulphuric acids, obtained by reacting molar quantities of aliphatic alcohols containing from about 6 to about 18 carbon atoms with from about 1 to about 15 moles of ethylene oxide, or a suitable mixture of ethylene oxide and propylene oxide, and subsequently reacting the alkoxylated alcohol with sulphur trioxide to yield the required acid; and alpha-sulphonated natural or synthetic aliphatic carboxylic acids, particularly those derived from natural sources such as tallows, coconut oil, palm oil, palm kernel oil and groundnut oil.

Suitable nonionic detergent-active compounds fall into several different chemical types. These are generally polyoxyethylene condensates of organic compounds having reactive hydrogen atoms. Examples of suitable nonionic detergent-active compounds are:

a. Polyoxyethylene condensates of aliphatic carboxylic acids, whether linear or branched-chain and unsaturated or saturated, containing from about 8 to about 18 carbon atoms in the aliphatic chain and incorporating from 5 to about 50 ethylene oxide units. Suitable carboxylic acids include coconut fatty acid (derived from coconut oil) which contains on average about 12 carbon atoms, tallow" fatty acid (derived from tallow-class fats) which contains on average about 18 carbon atoms, palmitic acid, myristic acid, stearic acid and lauric acid.

b. Polyoxyethylene condensates of primary or secondary aliphatic alcohols, whether linearor branchedchain and unsaturated or saturated, containing from about 8 to about 24 carbon atoms and incorporating from about 5 to about 50 ethylene oxide units. Alcohols containing about 8 to about 1 8 carbon atoms, and condensates incorporating not more than about 20 ethylene oxide units, are preferred. Suitable alcohols include coconut fatty alcohol (derived from coconut oil), tallow fatty alcohol (derived from tallow-class fats), lauryl alcohol, myristyl alcohol and oleyl alcohol.

0. Polyoxyethylene condensates of alkyl phenols, whether linear or branched chain, wherein the alkyl chain contains about 6 to 18 carbon atoms, incorporating from about 5 to 50 ethylene oxide units. Alkyl phenols wherein the alkyl chain contains about 8 to 16 carbon atoms, and condensates incorporating not more than about 20 ethylene oxide units, are preferred. Suitable alkyl phenols include nonyl phenol, decyl phenol, dodecyl phenol, tetradecyl phenol and hexadecyl phenol. This particular group of nonionic detergent-active compounds tend to be less biodegradable, and consequently are less preferred.

Further examples of suitable anionic and nonionic detergent-active compounds commonly used in the art are given in Surface Active Agents, Volume I" by Schwartz and Perry (Interscience 1949) and Surface Active Agents, Volume II by Schwartz, Perry and Berch (Interscience 1958 the disclosures of which are included by reference herein.

In general, a controlled-su dsing detergent composition of the invention will contain one or more detergency builders, usually in an amount of from about 5 to about 70% by weight of the detergent composition. Many detergency builders are known, and those skilled in the art of formulating fabric-washing detergent compositions will be familiar with these materials. Examples of known detergency builders are sodium tripolyphosphate; sodium orthophosphate; sodium pyrophosphate; sodium trimetaphosphate; sodium ethane-1- hydroxyl 1 diphosphonate; sodium carbonate; sodium silicate; sodium citrate; sodium oxydiacetate; sodium carboxymethyl oxysuccinate; sodium nitrilotriacetate; sodium ethylenediaminetetraacetate; sodium salts of long-chain dicarboxylic acids, for instance straight chain (C to C succinic acids and malonic acids; sodium salts of alpha-sulphonated long-chain monocarboxylic acids; sodium salts of polycarboxylic acids, i.e., acids derived from the polymerisation or copolymerisation of unsaturated carboxylic acids and unsaturated carboxy acid anhydrides such as maleic acid, acrylic acid, itaconic acid, methacrylic acid, crotonic acid and aconitic acid, and the anhydrides of these acids, and also from the copolymerisation of the above acids and anhydrides with minor amounts of other monomers, such as vinyl chloride, vinyl acetate, methyl methacrylate, methyl acrylate and styrene; and modified starches such as starches oxidised, for example using sodium hypochlorite, in which some anhydroglucose units have been opened to give dicarboxyl units. In some instances, the free acid form of the above sodium salts, or alternatively other salts such as potassium salts, may be employed.

In addition to the detergent-active component and detergency builders, a controlle d-sudsing detergent composition of the invention may contain any of the conventional fabric-washing detergent composition ingredients in any of the amounts in which such conventional ingredients are usually employed therein. Examples of these additional ingredients are inorganic salts (fillers) such as sodium sulphate and magnesium sulphate; bleaching agents such as sodium perborate, sodium percarbonate, trichloroisocyanuric acid, and sodium and potassium dichloroisocyanurates; antiredeposition agents, such as sodium carboxymethylcellulose; and, usually present only in minor amounts, perfumes, colourants, fluorescers, corrosion inhibitors, germicides and enzymes.

A controlled-sudsing detergent composition of the invention can be prepared using any of the conventional manufacturing techniques commonly used or proposed for the preparation of fabric-washing detergent compositions, such as slurry-making followed by spray-drying or spray-cooling, and subsequent drydosing of sensitive ingredients not suitable for incorporation prior to the drying step. Other conventional techniques, such as noodling, granulation, and mixing by fluidisation in a fluidised bed, may be utilised as and when necessary. Such techniques are familiar to those skilled in the art of fabric-washing detergent composition manufacture.

By using such conventional manufacturing techniques, a controlled-sudsing detergent composition of the invention may be prepared in any of the common physical forms associated with fabric-washing detergent compositions, such as powders, flakes, granules, noodles, cakes and, in some cases, liquids.

The invention is further illustrated in the following Examples.

EXAMPLES l to 3 Three controlled-sudsing (medium-sudsing) fabricwashing detergent powders wereprepared by conventional slurry-making, spray-drying and dry-dosing techniques, and had the following essential formulation:

The sodium soap components in the three powders were made up of soaps derived from different blends of commercially'availablc fatty acid mixtures. as follows:

-Continued Component (by weight) Example 1: equal proportions of Prifac 003", Prifac 314 and hardened herring oil fatty acids.

Example 2: 40% Prifac 003, 30% "Prifac 314 and 30% hardened herring oil fatty acids.

Example 3: 20%-Prifac 003, 30% Prifac 314". 30% hardened herring oil fatty acids, and 20% byproduct volatile fatty acids.

The actual fatty acid contents of these various fatty acid mixtures were as follows:

Obtainablc from Price's Chemicals Ltd, Brombornugh. Cheshire. "obtainable from Lever Brothers Ltd., Warrington, Lancashire.

Hence the fatty acid blends used in the soaps were:

Table II Fatty Acid Type Example Saturated Saturated Saturated Unsaturated C16 lG-IB C18 Each of the three detergent powders were used to wash a 9 lb load of domestically-soiled laundry articles in a tumbler-type front-loading drum washing machine fitted with an inspection port-hole in the door.

The normal operating cycle of the washing machine was followed. 4.7 gallons of 24 hard (CazMg ratio 23:1) was used in the pre-wash and also in the main wash. 150 g of the detergent powder being tested was added at the pre-wash stage. After the pre-wash, the wash liquor was emptied but the load was not rinsed. A further 150 g of the detergent powder was added during the main wash. During the main wash, the wash liquor was heated and the temperature rose linearly from 20C to 90C over a period of one hour.

The lathering properties of the detergent powder were assessed by measuring the lather height visible through the washing machine port-hole. The level of the wash liquor was visible near the bottom of the porthole, and this was used as a reference point, the lather height being measured in inches above this point. A lather height of 14 inches was considered to be a safe maximum.

As a Control, a commercially-available controlledsudsing detergent powder was tested by the same procedure.

The following results were obtained during two tests with the detergent powder of Example 1:

Table III Lather height (inches) Time from start of main Wash Test 1 Test 2 (minutes) Ex- Example 1 Control ample 1 Control 5 3 Trace 2 Trace 10 I 1 Trace 6 Trace l5 12 0.5 10 0.5 20 12 0.5 13 0.5 25 8 0.5 6 0.5 30 7 0.5 7 0.5 35 4 1 8 1 4O 7 2 6 0.5 45 8 2 9 2 50 12 3 9 5- 55 13 6 8 6 60 9 7 12 7 Comparable results were obtained with the detergent powders of Examples 2 and 3.

The above results show that the detergent powders of the invention, when used at product concentrations sufficient to give excellent detergency, produced at all temperatures within the operating range a quantity of suds which was sufficient to be visible readily through the port-hole but was not so high as to cause any danger of oversudsing.

EXAMPLES 4 to 6 Three controlled-sudsing fabric-washing detergent powders were prepared as in Examples 1 to 3, and had the following essential formulations:

Component 7: (by weight) Example 4: equal proportions of"Prifac 003". "Prifac 314" and hardened herring oil fatty acids.

Example 5: 40% Prifac 003". 30% Prifac 314" and 30% hardened herring oil fatty acids. 7 Example 6: 20% "Prifac 003", 30% Prifac 314", 30% hardened herring fatty acids, and 20% by-product volatile fatty acids.

These three detergent powders were tested as in Examples l to 3. Similar results were obtained.

What is claimed is:

- l. A blend of fatty acids which blend is suitable for use in the form of a soap as an ingredient of a controlled sudsing fabric washing detergent composition and which blend consists of by weight:

a. From about 31.7 to about 40% of saturated fatty acids containing less than 16 carbon atoms,

b. From about 28.1 to about 32.3% of saturated fatty acids containing from 16 to 18 carbon atoms,

0. From about 14.4 to about l6% of saturated fatty acids containing more than 18 carbon atoms, and

d. From about 17.5 to about 20% of unsaturated fatty acids containing on average more than about 16 carbon atoms.

2. A sodium soap derived from a blend of fatty acids b. From about 4 to about 5% of sodium soap, accordlng to Clam c. About 3% of a tallow alcohol 18EO ethoxylate de- 3. A oontrolled-sudsing fabric-washing detergent tergent active Compound and composmon consisting essentially of by weight: d A 327 f l h h a. From about 9 to about 10% by weight ofa sodium 5 bout 0 9 so mp0 05p Sal alkyl benzene sulphonate detergent-active comdlum Soap bemg a p accordmg to Pound, 

2. A sodium soap derived from a blend of fatty acids according to claim
 1. 3. A controlled-Sudsing fabric-washing detergent composition consisting essentially of by weight: a. From about 9 to about 10% by weight of a sodium alkyl benzene sulphonate detergent-active compound, b. From about 4 to about 5% of sodium soap, c. About 3% of a tallow alcohol 18EO ethoxylate detergent-active compound, and d. About 32% of sodium tripolyphosphate, said sodium soap being a soap according to claim
 2. 